Effect of electrical stimulation on the fusion rate after spinal surgery: a systematic review and meta-analysis.

Electrical stimulation is an important adjuvant therapy for spinal surgery, but whether receiving electrical stimulation can improve the fusion rate after spinal surgery is still controversial. The purpose of this study was to analyse and evaluate the effect of electrical stimulation on the fusion rate after spinal surgery. We systematically searched for related articles published in the PubMed, Embase and Cochrane Library databases on or before September 30, 2023. The odds ratio (OR) with 95% confidence interval (CI) and the fusion rates of the experimental group and the control group were calculated by a random-effects meta-analysis model. The analysis showed that receiving electrical stimulation significantly increased the probability of successful spinal fusion (OR 2.66 [95% CI 1.79-3.97]), and the average fusion rate of the electrical stimulation group (86.8%) was significantly greater than that of the control group (73.7%). The fusion rate in the direct current (DC) stimulation group was 2.33 times greater than that in the control group (OR 2.33 [95% CI 1.37-3.96]), and that in the pulsed electromagnetic field (PEMF) group was 2.60 times greater than that in the control group (OR 2.60 [95% CI 1.29-5.27]). Similarly, the fusion rate in the capacitive coupling (CC) electrical stimulation group was 3.44 times greater than that in the control group (OR 3.44 [95% CI 1.75-6.75]), indicating that regardless of the type of electrical stimulation, the fusion rate after spinal surgery improved to a certain extent. Electrical stimulation as an adjuvant therapy seems to improve the fusion rate after spinal surgery to a certain extent, but the specific effectiveness of this therapy needs to be further studied.

The impact of sarcopenia on the incidence of postoperative outcomes following spine surgery: Systematic review and meta-analysis.

PURPOSE: Sarcopenia is considered to be an important predictor of adverse outcomes following spinal surgery, but the specific relationship between the two is not clear. The purpose of this meta-analysis is to systematically review all relevant studies to evaluate the impact of sarcopenia on spinal surgery outcomes. METHODS: We systematically searched PubMed, Embase and the Cochrane Library for relevant articles published on or before January 9, 2023. The pooled odds ratio (OR) with 95% confidence intervals (CIs) was calculated in a random effects meta-analysis. The main outcome was the risk of adverse outcomes after spinal surgery, including adverse events and mortality. This systematic review and meta-analysis was conducted following the PRISMA guidelines to evaluate the impact of sarcopenia on spinal surgery outcomes. In addition, we also conducted a subgroup analysis and leave-one-out sensitivity analyses to explore the main sources of heterogeneity and the stability of the results. RESULTS: Twenty-four cohort studies, with a total of 243,453 participants, met the inclusion criteria. The meta-analysis showed that sarcopenia was significantly associated with adverse events (OR 1.63, 95% CI 1.17-2.27, P < 0.001) but was no significantly associated with mortality (OR 1.17, 95% CI 0.93-1.46, P = 0.180), infection (OR 2.24, 95% CI 0.95-5.26, P < 0.001), 30-day reoperation (OR 1.47, 95% CI 0.92-2.36, P = 0.413), deep vein thrombosis (OR 1.78, 95% CI 0.69-4.61, P = 0.234), postoperative home discharge (OR 0.60, 95% CI 0.26-1.37, P = 0.002) and blood transfusion (OR 3.28, 95% CI 0.74-14.64, P = 0.015). CONCLUSION: The current meta-analysis showed that patients with sarcopenia have an increased risk of adverse events and mortality after spinal surgery. However, these results must be carefully interpreted because the number of studies included is small and the studies are significantly different. These findings may help to increase the clinicians' awareness of the risks concerning patients with sarcopenia to improve their prognosis.

Risk factors affecting spinal fusion: A meta-analysis of 39 cohort studies.

PURPOSE: We performed a meta-analysis to identify risk factors affecting spinal fusion. METHODS: We systematically searched PubMed, Embase, and the Cochrane Library from inception to January 6, 2023, for articles that report risk factors affecting spinal fusion. The pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using fixed-effects models for each factor for which the interstudy heterogeneity I2 was < 50%, while random-effects models were used when the interstudy heterogeneity I2 was ≥ 50%. Using sample size, Egger's P value, and heterogeneity across studies as criteria, we categorized the quality of evidence from observational studies as high-quality (Class I), moderate-quality (Class II or III), or low-quality (Class IV). Furthermore, the trim-and-fill procedure and leave-one-out protocol were conducted to investigate potential sources of heterogeneity and verify result stability. RESULTS: Of the 1,257 citations screened, 39 unique cohort studies comprising 7,145 patients were included in the data synthesis. High-quality (Class I) evidence showed that patients with a smoking habit (OR, 1.57; 95% CI, 1.11 to 2.21) and without the use of bone morphogenetic protein-2 (BMP-2) (OR, 4.42; 95% CI, 3.33 to 5.86) were at higher risk for fusion failure. Moderate-quality (Class II or III) evidence showed that fusion failure was significantly associated with vitamin D deficiency (OR, 2.46; 95% CI, 1.24 to 4.90), diabetes (OR, 3.42; 95% CI, 1.59 to 7.36), allograft (OR, 1.82; 95% CI, 1.11 to 2.96), conventional pedicle screw (CPS) fixation (OR, 4.77; 95% CI, 2.23 to 10.20) and posterolateral fusion (OR, 3.63; 95% CI, 1.25 to 10.49). CONCLUSIONS: Conspicuous risk factors affecting spinal fusion include three patient-related risk factors (smoking, vitamin D deficiency, and diabetes) and four surgery-related risk factors (without the use of BMP-2, allograft, CPS fixation, and posterolateral fusion). These findings may help clinicians strengthen awareness for early intervention in patients at high risk of developing fusion failure.

Risk factors of postoperative delirium following spine surgery: A meta-analysis of 50 cohort studies with 1.1 million participants.

Objectives: Postoperative delirium (POD) is considered to be a common complication of spine surgery. Although many studies have reported the risk factors associated with POD, the results remain unclear. Therefore, we performed a meta-analysis to identify risk factors for POD among patients following spinal surgery. Methods: We systematically searched the PubMed, Embase and the Cochrane Library for relevant articles published from 2006 to February 1, 2023 that reported risk factors associated with the incidence of POD among patients undergoing spinal surgery. The Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines were followed, and random effects models were used to estimate pooled odds ratio (OR) estimates with 95 % confidence intervals (CIs) for each factor. The evidence from observational studies was classified according to Egger's P value, total sample size, and heterogeneity between studies. Results: Of 11,329 citations screened, 50 cohort studies involving 1,182,719 participants met the inclusion criteria. High-quality evidence indicated that POD was associated with hypertension, diabetes mellitus, cardiovascular disease, pulmonary disease, older age (>65 years), patients experiencing substance use disorder (take drug ≥1 month), cerebrovascular disease, kidney disease, neurological disorder, parkinsonism, cervical surgery, surgical site infection, postoperative fever, postoperative urinary tract infection, and admission to the intensive care unit (ICU). Moderate-quality evidence indicated that POD was associated with depression, American Society of Anesthesiologists (ASA) fitness grade (>II), blood transfusion, abnormal potassium, electrolyte disorder, length of stay, inability to ambulate and intravenous fluid volume. Conclusions: Conspicuous risk factors for POD were mainly patient- and surgery-related. These findings help clinicians identify high-risk patients with POD following spinal surgery and recognize the importance of early intervention.

The impact of perioperative opioid use on postoperative outcomes following spinal surgery: a meta-analysis of 60 cohort studies with 13 million participants.

BACKGROUND CONTEXT: An important factor for the prognosis of spinal surgery is the perioperative use of opioids. However, the relationship is not clear. PURPOSE: The purpose of this study was to evaluate the effect of perioperative opioid use on the prognosis of patients following spinal surgery. STUDY DESIGN/SETTING: Systematic review and meta-analysis. OUTCOME MEASURES: A meta-analysis was conducted using the random-effects method to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs). METHODS: The PubMed, Embase, and Cochrane Library databases were systematically searched to find relevant articles that were published until September 2, 2022. The primary outcome was prolonged postoperative opioid use, and secondary outcomes included the length of stay (LOS), reoperation, the time to return to work (RTW), postoperative complications, gastrointestinal complications, new permanent disability, central nervous system events and infection. In addition, subgroup analysis of the primary outcome was conducted to explore the main sources of heterogeneity, and sensitivity analysis of all outcomes was performed to evaluate the stability of the results. RESULTS: A total of 60 cohort studies involving 13,219,228 individuals met the inclusion criteria. Meta-analysis showed that perioperative opioid use was specifically related to prolonged postoperative opioid use (OR 6.91, 95% CI 6.09 to 7.84, p<.01). Furthermore, the results also showed that perioperative opioid use was significantly associated with prolonged LOS (OR 1.74, 95% CI 1.39 to 2.18, p<.01), postoperative complications (OR 1.72, 95% CI 1.26 to 2.36, p<.01), reoperation (OR 2.38, 95% CI 1.85 to 3.07, p<.01), the time to RTW (OR 0.45, 95% CI 0.39 to 0.52, p<.01), gastrointestinal complications (OR 1.39, 95% CI 1.30 to 1.48, p<.01), central nervous system events (OR 1.99, 95% CI 1.21 to 3.27, p=.07) and infection (OR 1.22, 95% CI 1.09 to 1.36, p=.01). These results were corroborated by the trim-and-fill procedure and leave-one-out sensitivity analyses. CONCLUSIONS: Based on the current evidence, patients with perioperative opioid use, in comparison to controls, appear to have prolonged postoperative opioid use, which may increase the risk of poor outcomes including prolonged LOS, complications, reoperation, RTW and so on. However, these results must be carefully interpreted as the number of studies included was small and the studies were statistically heterogeneous. These findings may help clinicians to realize the harmfulness of perioperative use of opioids, reduce the use of prescription opioids, necessarily withdraw before operation or significantly wean to the lowest tolerable preoperative amount, and provide some inspiration for standardizing the use of opioids in the future.

Risk factors for lumbar disc herniation recurrence after percutaneous endoscopic lumbar discectomy: a meta-analysis of 58 cohort studies.

Recurrent lumbar disc herniation (rLDH) is one of the most serious complications and major causes of surgical failure and paralysis following percutaneous endoscopic lumbar discectomy (PELD). There are reports in the literature on the identification of risk factors associated with rLDH; however, the results are controversial. Therefore, we conducted a meta-analysis to identify risk factors for rLDH among patients following spinal surgery. PubMed, EMBASE, and the Cochrane Library were searched without language restrictions from inception to April 2018 for studies reporting risk factors for LDH recurrence after PELD. MOOSE guidelines were followed in this meta-analysis. We used a random effects model to aggregate odds ratios (ORs) with 95% confidence intervals (CIs). The evidence of observational studies was classified into high quality (class I), medium quality (class II/III), and low quality (class IV) based on the P value of the total sample size and heterogeneity between studies. Fifty-eight studies were identified with a mean follow-up of 38.8 months. Studies with high-quality (class I) evidence showed that postoperative LDH recurrence after PELD was significantly correlated with diabetes (OR, 1.64; 95% CI, 1.14 to 2.31), the protrusion type LDH (OR, 1.62; 95% CI, 1.02 to 2.61), and less experienced surgeons (OR, 1.54; 95% CI, 1.10 to 2.16). Studies with medium-quality (class II or III) evidence showed that postoperative LDH recurrence was significantly correlated with advanced age (OR, 1.11; 95% CI, 1.05 to 1.19), Modic changes (OR, 2.23; 95% CI, 1.53 to 2.29), smoking (OR, 1.31; 95% CI, 1.00 to 1.71), no college education (OR, 1.56; 95% CI, 1.05 to 2.31), obesity (BMI ≥ 25 kg/m2) (OR, 1.66; 95% CI, 1.11 to 2.47), and inappropriate manual labor (OR, 2.18; 95% CI, 1.33 to 3.59). Based on the current literature, eight patient-related and one surgery-related risk factor are predictors of postoperative LDH recurrence after PELD. These findings may help clinicians raise awareness of early intervention for patients at high risk of LDH recurrence after PELD.

Risk factors of epidural hematoma in patients undergoing spinal surgery: a meta-analysis of 29 cohort studies.

OBJECTIVE: The authors conducted this meta-analysis to identify risk factors for spinal epidural haematoma (SEH) among patients following spinal surgery. METHODS: The authors systematically searched Pub: Med, Embase, and the Cochrane Library for articles that reported risk factors associated with the development of SEH in patients undergoing spinal surgery from inception to 2 July 2022. The pooled odds ratio (OR) was estimated using a random-effects model for each investigated factor. The evidence of observational studies was classified as high quality (Class I), moderate quality (Class II or III) and low quality (Class IV) based on sample size, Egger's P value and between-study heterogeneity. In addition, subgroup analyses stratified by study baseline characteristics and leave-one-out sensitivity analyses were performed to explore the potential sources of heterogeneity and the stability of the results. RESULTS: Of 21 791 articles screened, 29 unique cohort studies comprising 150 252 patients were included in the data synthesis. Studies with high-quality evidence showed that older patients (≥60 years) (OR, 1.35; 95% CI, 1.03-1.77) were at higher risk for SEH. Studies with moderate-quality evidence suggested that patients with a BMI greater than or equal to 25 kg/m² (OR, 1.39; 95% CI, 1.10-1.76), hypertension (OR, 1.67; 95% CI, 1.28-2.17), and diabetes (OR, 1.25; 95% CI, 1.01-1.55) and those undergoing revision surgery (OR, 1.92; 95% CI, 1.15-3.25) and multilevel procedures (OR, 5.20; 95% CI, 2.89-9.37) were at higher risk for SEH. Meta-analysis revealed no association between tobacco use, operative time, anticoagulant use or American Society of Anesthesiologists (ASA) classification and SEH. CONCLUSIONS: Obvious risk factors for SEH include four patient-related risk factors, including older age, obesity, hypertension and diabetes, and two surgery-related risk factors, including revision surgery and multilevel procedures. These findings, however, must be interpreted with caution because most of these risk factors had small effect sizes. Nonetheless, they may help clinicians identify high-risk patients to improve prognosis.